The present invention relates to a tool equipped with a locking device in at least one position of a mobile portion of the tool.
The term “tool” designates here, in the broad sense, a tool provided with at least one mobile element forming an active portion of the tool. It may be a hand tool such as a folding knife, a saw, a shovel or a hand tool with a blade. This term also relates to a tool such as a handle, a measuring instrument, a handling tool or more generally a tool of which at least one active portion is configured as a mobile element between a so-called inactive position in which the element is, for example, inserted in a dedicated housing and/or in which the tool has a minimum volume and a so-called active position in which the element is usable and/or the tool has a maximum volume.
Subsequently, the invention will be described with reference to a hand tool of the folding knife type, it being understood that the invention may be applied to all types of tools as described above.
We know of hand tools, such as a closing knife, of which an active part, for example a blade or a corkscrew or a screwdriver-type accessory, is maintained, for safety reasons, locked in at least one position, namely at least the active position. Thus, it avoids accidental closure of the knife, so any non-voluntary folding of the blade in its housing. The locking devices are varied, some being adapted to also lock the mobile portion of the tool in the inactive position.
These various devices must be simple to manufacture, reliable and easy to use.
For example, US Patent A-2013/0236236 discloses a device locking the rails of a ladder in position. The device is integrated to a rail. It comprises a complex-shaped cutout of one end of the rail, so as to define a movable locking member by spring effect. The end of the member, according to the occupied position, engages with one of the notches provided on the end of the other rail, locking the latter in a given position, namely with folded or unfolded rails. We also know of folding knives whose blade is kept locked in at least the open position by a part, of the lever or push type.
This part comprises an end adapted to engage with a notch provided in the heel of the blade. The maneuver and/or the return of the part into position is ensured by spring effect. Such knives are, for example, described in US Patent A-2017/0136634; US Patent A-2016/0354936; US Patent A-2016/0279810. Such solutions involve the manufacture and assembly of a relatively large number of parts, with dimensional constraints involving an assembly carried out by an experienced person, so, at least in part, difficult to automate. These points therefore have an impact on the cost of manufacturing and the time required to produce such tools. US Patent A-2011/0119926 discloses a folding knife whose blade is held in position by a part formed by folding, said part being mobile by means of a deformable arm and also integral with the part. Such a solution does not allow a pivoting movement that is optimized, precise and minimizes the risk of deformation of the arm.